Thermostat valve structure



Nov. 11, 1930. GRAYSON 1,781,328

THERMOSTAT VALVE STRUCTURE Filed June 28, 1929 2 Sheets-Sheet lINVENTOR.

A TTORNEY5 Nov. 11, 1930. J. H. GRAYSON 1,781,328

THERMOSTAT VALVE S TRUCTURE Filed June-28, 1929 2 Sheets-Sheet 2 INVENTOR. BY /o/w /7. 6/65/50 @QJMMM A TTORNEYS.

Patented Nov. 11, 1930 PATENT OFFICE JOHN H. GRAYSON, OF L'YNWOOD,CALIFORNIA THERMOSTAT VALVE STRUCTURE Application fled June 28, 1929.Serial No. 874,525.

This invention relates to thermostats such as are especially adapted touse with water heaters, oven regulators and like devices wherein a fluidfuel flow is controlled. It

6 is especially adapted to the control of gaseous fuel. Such thermostatshave been constructed with a casing serving= as a housing for a valveand snap mechanism to actuate the valve.

The objects of this invention are to rovide a thermostat of thecharacter described which is compact; has a fuel valve and valve seatwhich is resistant to warping and corrosion; is easy of assembly andeconomical to manufacture; and wherein provision is made for directconnection thereto of the pilot burner service tubing.

These objects are accomplished by means of the embodiments of myinvention illustrated in the accompanying drawings, in which Fig. lrisa' vertical section through a fragment of a water heater showing thelower thereof provided with a main burner, a pilot burner and athermostat control in elevation; Fig. 2 is asection as seen on the line2-2 I of Fig. 1; Fig. 3 is an enlarged view partly in section of thepilot burner connection; Fig. 4 is a section as seen on the line 4-4 ofFig. 2; Figs. 5 and 6 are sections as seen on the lines correspondinglynumbered in Fig. 4; and Fig. 7 is a perspective view of the valve seatbushing snap action diaphragm disk and amplifier.

It will be understood that although the invention is described herein asapplied to a water heater, it is in no way limited to such application.The specific application disclosed herein is for illustrative purposesonly.

Referring more particularly to Fig. 1 A indicates a heater tank having abottom defining the upper wall of a heater chamber, in which is disposeda main burner B. The burner is supplied with gas by a pipe connected toa thermostat valve structure C. The pilot burner is indicated generallyby D and has a service supply pipe connected to the thermostat valvecontrol structure G.

The present invention resides particularly in the thermostat valvecontrol structure C.

The valve control comprises a body or casing 10 having an inletextension 11 and an outlet extension 12 in alinement. A cylindrical bore13 extends through the casing transverse to the line of the inlet andoutlet.

A cylindrical wall 14 is provided for separating the inlet from theoutlet and has an opening 15 communicating with the inlet and an opening16 with the outlet. An annular recess is formed in the wall 14 and ismarked 17. The body is provided with a yoke extension 18 havin acylindrical head 19 externally threaded to adapt it to be mounted in theshell of the tank A. The inlet and outlet extensions are tapped toreceive respectively inlet and outlet pipes 20 and 21. The bore is alsotapped at one end to receive a cap 22 which is preferably provided withflat sides so as to form a wrench hold. A protuberance or boss 23 isprovided on the casing having a port 24 communicating with the inlet endof the bore 13. A conical seat 25 is formed in the port for a rotaryvalve plug. The outer end of the port- 25 is enlarged as indicated by 26and threaded to receive a closure plug 34. Extending laterally of theport 24 an communicating with the valve seat portion 25 is a passage 27enlarged as indicated by 28 to receive a pilot burner service tube 29leading to the pilot burner D. Loosely disposed in the seat 25 is avalve plug 30 having a central bore 31 communicating with the inletchamber portion of bore 13 through port as 24, and having a lateralopening 32 for. registration with the passage 27. The seat and plug havea taper of approximately fourteen degrees, as it has been found thatwith this taper when the valve plug is forced, it will remain in the setposition. A stem 33 is provided on the plug and extends through the borein a closure plug 34 so that the valve plug may be turned and the amountof gas supplied to the pilot burner controlled thereby. The enlargedportion 26 of the port has threaded therein the closure lug 34. Stem 33has a kerf for reception 0 the blade of a screw driver so that the valveplug may be turned.

The simplicity of the structure is apparent. Onl the thermostat valvecontrol is Inserted in t e gas line to the main burner. It is notnecessary to break the line in order to place fittings of any nature forthe pilot burner pigs with the present invention.

he casing is preferably made of cast brass. Disposed in the bore 13 1s avalve seat bushing 36. This bushing is preferably formed of rolled brasswhich is more dense and will not corrode with the various gases commonlyused for fuel, as would cast brass. The bushing serves as a combinationvalve seat, valve stem guide and has annular shoulders for supportingthe amplifier and a disk springl diaphra The bushing is preferably helin place a pressed, fit and has ports 37 registering with the recess 17and with the outlet. The bushing has a ported web 38 extending acrossthe inner end and is provided with a raised portion 39 so as to form avalve seat. A boss 40 is bored to form a valve stem uide. At the outerend of the bushing a edge 41 is provided. The valve stem 42 is slidablymounted in the boss and is reduced in diameter to provide a shouler fora valve disk 43 to rest against. A follower 44 is slidably mounted onthe reduced portion of the stem and has an outstanding flange serving asa seat for a compression spring 45 resting against the cap 22 at itsother end. The compression spring acting against the follower 44 tendsto hold the valve disk on its seat closing communication between theinlet and outlet sides of the casing. The valve stem has at its outerend an adjustable extension 46 which is threaded into the main body ofthe valve stem, so that the length of the valve stem may be adjusted.Mounted upon the shoulder 41 so as to loosely rest thereon is a valvedisk diaphragm 47 formed of any suitable resilient material, such as aGerman silfi ver alloy, spring bronze or material of suchcharacteristics that it may be dished as shown and the center may besmoothed inwardly past said center and will snap over without anypermanent set. Restingupon the outer end of the bushing is an am lifier48 stamped from a single sheet to provlde a ring and inwardly extendinglever arms 49 and 49 The free ends of the lever are indented to provideprotuberances 50 and 50 for bearing upon the center of the snap disk 47.A follower plunger 51 has a rib dis osed to bear upon the lever armsadjacent tieir fulcrum points. The plunger is a disk slidably mounted inthe bore 13. A concavity is formed at the center thereof to receive arod 52. This rod is preferably made of invar which is sub-,

stantially free from contraction and expansion under temperaturechanges. It is adjustably mounted b means of a thread in a plug 53secured to the outer end of a tube 54. The tube 54 is made of a materialhaving a relatively high coefiicient of expansion, such as copper, thistube is secured at its inner end in the head 19. Due to the diiferencein the coefficients of expansion of the rod 52 and the tube 54,expansion and contraction of the tube 54 will cause slight endwis'emovement of the rod 52. In order that the rod may be adjustedexternally, I have shown aflixed thereto a lever 55 extending throughthe opening in the yoke and arranged to be swung over a dial or scalemarked on the valve casing body.

The tube 54 extends into the tank and is in contact with the watertherein. Upon lowering of temperature in the tank, tube 54 contacts andmoves rod 52 toward the plunger 51, exerting pressure upon the leverarms 49 and 49 The movement is amplified by the levers and transmittedto the center of the snap disk 47. Assuming the latter is in theposition shown in Fig. 4, suflicient movement of the rod 42 will causethe center of the disk to be snapped over dead center, the movement ofthe disk being finally completed by its resiliency. The disk acts uponthe valve stem 42 against the action of comv The bushing 36 can e easilyand accurate,

1y machined and pressed into place without distortion. It is formed of amaterial which is resistant to corrosion and warping. It forms the valvestem guide, the valve seat and a shoulder for snap disks or the ampli-What I claim is p 1. A thermostat valve control structure comprising acasing having an inlet for supply of gas an outlet for a main burner, abore extending through said casing connecting said inlet and outlet, abushing inserted in said bore dividing said casing into an inlet chamberand an outlet chamber connected respectively to said inlet and saidoutlet, a valve seat provided in said bushin for communication of saidinlet and .out et chambers, a gas valve controlling the ports in saidseat, said bushing having a ledge at its outer end adapted for seatingthereon of a valve actuator.

2. A thermostat valve control structure ill let, a valve seat providedin the inner end of said bushing for communication of said inlet andoutlet chambers, a poppet gas valve controlling the ports in said seatand having a stem, a boss in the inner end of said bushing having a boreextending therethrough to form a guide for said stem, said bushinghaving a ledge at its outer end adapted for seating thereon of a valveactuator.

3. A thermostat valve control structure comprising a casing having aninlet for supply of gas, an outlet for a main burner, a bore extendingthrough said casing transverse to said inlet and outlet, a bushinghaving a transverse wall, said bushing being inserted in said bore anddividing said casing intoan inlet chamber and an outlet chamberconnected respectively to said inlet and said outlet, a valve seatrovided in said wall for communication 0 said inlet and said outletchambers, a poppet gas valve controlling the ports of said seat having astem, a shoulder at the outer end of said bushing, a snap disk looselyseated on said shoulder and adapted to engage said stem to operate saidvalve, a rim on said bushing beyond said shoulder, an amplifier seatedon said rim having inwardly extending lever arms to engage said snapdisk at their free ends, and means to swing said levers mounted on saidcasing.

4. A thermostat valve control structure comprising a casing having aninlet for supply of gas, an outlet for a main burner, a bore extendingthrough said casing transverse to said inlet and outlet, a bushinghaving a transverse wall inserted in said boredividing said casing intoan inlet chamber and an outlet chamber connected respectively to saidinlet and said outlet, valve ports in said wall for communication ofsaid inlet and outlet chambers, a poppet gas valve controlling saidports having a stem, a shoulder at the outer end of said bushing, a snapdisk loosely seated on said shoulder and adapted to engage said stem tooperate said valve, a rim in said bushing beyond said shoulder, anamplifier seated on said rim having inwardly extending lever arms toengage said snap disk at their free ends, a follower plunger slidablymounted in said bore, and having a bearing on said arms adjacenttheirjulcrums, and thermally operated means to move said plunger andthereby to swing said levers.

5. A thermostat valve control structure comprising a casing having aninlet for supply of gas, an outlet for a main burner, a

ore extending through said casing transverse to said inlet and outlet,an annular web disposed between said inlet and outlet having ofi'setlateral openings communicating respectivel with said inlet and saidoutlet, a bushing inserted in said bore and having a transverse walldisposed between said opening and dividing said casing into an inletchamber and an outlet chamber, an

annular internal recess in said web, openings in the circumferentialwall of said bushing communicating with said recess, valve ports in saidwall for communication of said inlet and outlet chambers, a poppet gasvalve contnolling said ports having a stem, a shouldei' at the outer endof said bushing, a snap disk loosely seated on said shoulder and adaptedto engage said stem to operate said valve, a rim on said bushing beyondsaid shoulder, an amplifier seated on said rim having inwardly extendinglever arms to engage said snap disk at their free ends, and means toswing said lever mounted on said casing.

6. A thermostat valve control structure comprising a casing having aninlet for supply of gas, an outlet for a main burner, a bore extendingthrough said casing transverse to said inlet and outlet, an annular webbetween said inlet and outlet having ofi'set lateral openingscommunicating respectively with said inlet and said outlet a bushinginserted in said bore and having a transverse wall disposed between saidopening and dividing said casing into an inlet chamber and an outletchamber, an annular internal recess in said Web, openings in thecircumferential wall of said bushing communicating with said recess,valve ports in said wall for communication of said inlet and outletchambers, a poppet gas valve controlling said ports having a stem, aledge at the outer end of said bushing, and a valve actuator mounted onsaid ledge and adapted to engage said stem to operate said valve.

7. A thermostat valve control structure comprising a casing having aninlet for supply of gas, an outlet for a main burner, a bore extendingthrough said casing transverse to said inlet and outlet, an annular webbetween said inlet and outlet having offset lateral openingscommunicating respectively with said inlet and outlet, a bushinginserted in said bore and having an inner wall disposed between saidopenings and dividing said casing into an inlet chamher and an outletchamber, an annular internal recess in said web, openings in thecircumferential wall of said bushing communicating with said recess,valve ports in said inner wall for communication of said inlet andoutlet chambers, a poppet gas valve controlling said ports having astem, a shoulder at the outer end of said bushing, a snap disk looselyseated on said shoularm adjacent their fulcrums and thermallyoperatedmeans to operate said plunger.

8. A thermostat valve control structure comprising a casing having aninlet for supply of gas, an outlet for a main burner, a ore extendingthrough said casing connecting said inlet and outlet, a bushing having atransverse wall, said bushing being inserted in said bore dividing saidcasing into an inlet chamber and an outlet chamber connectedrespectively to said inlet and said outlet, a valve seat provided insaid wall for communication of said inlet and said outlet chambers, apoppet gas valve controlling the ports of said seat and having a stem, ashoulder at the outer end of said bushing, a snap disk loosely seated onsaid shoulder and adapted to engage said stem to operate said valve, arim on said bushing beyond said shoulder, an amplifier seated on saidrim having inwardly extending lever arms tovengage said snap disk attheir free ends, and means to swing said levers mounted on said casing.

9. A thermostat valve control structure comprising a casing having aninlet for supply of gas, an outlet for a burner, a bore extendlngthrough said casing connecting said inlet and outlet, a bushing insertedin said bore dividing said casing into an inlet chamber and an outletchamber connected respectively to said inlet and said outlet, saidbushing having a port in the end thereof for communication of said inletand outlet chambers, a poppet gas valve controlling said port and havina stem, a boss in said bushing having a ore extending therethrough toform a guide for said stem, an annular ledge disposed at the end of saidbushing opposite to said port adapted for seating thereon of a valveactuator, a snap disk seated on said ledge and adapted to engage saidstem to operate said valve and thermostatic means to operate on saidsnap disk.

In witness that I claim the foregoing I have hereunto subscribed my namethis 20th day of May, 1929.

JOHN H. GRAYSON.

